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AIRTEMP vs ZEPHYR heat pumps
Measured against models of the same size and duct type, ZEPHYR scores higher on 5 of the 6 ratings. AIRTEMP has 25 outdoor models, ZEPHYR has 25 outdoor models. AIRTEMP and ZEPHYR have no QMID on file and are not ranked.
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CompareData as of updated · sources
Against comparable models
Each cell is the share of same-size, same-type models that the manufacturer’s typical model beats (50% is typical); the higher score is in bold. Raw medians are underneath for context: they depend on which sizes each one makes, so they are not compared.
- AIRTEMP
- ZEPHYR
- Other ranked manufacturers
Source: AHRI Directory, NEEP · as of
| Rating | AIRTEMP | ZEPHYR |
|---|---|---|
| Efficiency index | 45%median — | 58%median — |
| COP at 5°F | 32%median 1.81 | 40%median 1.87 |
| Capacity retention at 5°F | 65%median 77% | 68%median 80% |
| HSPF2 | 37%median 8.5 | 43%median 9.0 |
| SEER2 | 38%median 17.0 | 53%median 21.0 |
| EER2 | 44%median 11.0 | 52%median 12.5 |
| Heating capacity at 5°F | 63%median 19,800 Btu/h | 63%median 16,200 Btu/h |
| Outdoor models | 25 | 25 |
| AHRI certifications | 58 | 31 |
Share of models meeting each standard
| Standard | AIRTEMP | ZEPHYR |
|---|---|---|
| CEE 2025 Tier 1 (Split ASHP) | 48%12 models | 76%19 models |
| CEE 2026 Tier 1 (Split ASHP) | 48%12 models | 76%19 models |
| CEE Advanced Tier (Split ASHP) | 0%0 models | 0%0 models |
| Xcel Energy Colorado cold-climate ASHP (2025) | 52%13 models | 76%19 models |
| DOE Cold Climate Heat Pump Challenge | 0%0 models | 0%0 models |
| ENERGY STAR Cold Climate | 32%8 models | 36%9 models |
Sizes and duct types offered
Models in each peer group, with the efficiency index of those models against the rest of the group.
- AIRTEMP
- ZEPHYR
- All models of the group
Raw ratings are only placed side by side within one size and duct type, where they are comparable.
Source: AHRI Directory · as of
| Size and duct type | AIRTEMP | ZEPHYR |
|---|---|---|
| Ducted, up to 1.5 tons | 2 · index 31% | None |
| Ducted, 2 tons | 3 · index 53% | 1 · index 46% |
| Ducted, 2.5–3 tons | 6 · index 52% | 1 · index 63% |
| Ducted, 3.5–4.5 tons | 4 · index 63% | 2 · index 51% |
| Non-ducted, up to 1.5 tons | 8 · index 28% | 15 · index 58% |
| Non-ducted, 2 tons | 2 · index 57% | 4 · index 62% |
| Non-ducted, 2.5–3 tons | 5 · index 60% | 1 · index 70% |
| Non-ducted, 3.5–4.5 tons | None | 1 · index 45% |
Cold-climate and all-around picks, size class by size class
Each manufacturer’s best model on each board in every size and duct type, side by side; the higher score is in bold. Both scores are 0–100 against every model of that size class (the line on each bar is 50, the typical model there), so the two compare fairly even when they make different sizes.
Cold-climate picks
| Size and duct type | AIRTEMPCold-climate score, best model | ZEPHYRCold-climate score, best model |
|---|---|---|
| Ducted, up to 1.5 tons | 35.6(50 is the typical model of its size class)GXH18(5.3)FMK4DH-11 of 2 models qualify · AHRI 210276818 | No models in this size class |
| Ducted, 2 tons | 50.1(50 is the typical model of its size class)GXH24(7.0)FMK4DH-11 of 2 models qualify · AHRI 210276819 | 57.5(50 is the typical model of its size class) (higher)ZE-24HPBwith ducted air handler AH-24B1 of 1 models qualify · AHRI 207036640 |
| Ducted, 2.5–3 tons | 55.3(50 is the typical model of its size class)GXH24-36MSK4DHwith ducted air handler GMH**-36MSK4DH14 of 7 models qualify · AHRI 206724409 | 75.1(50 is the typical model of its size class) (higher)ZE-36HPBwith ducted air handler AH-36B1 of 1 models qualify · AHRI 207036642 |
| Ducted, 3.5–4.5 tons | 58.1(50 is the typical model of its size class) (higher)GXH48-60MSK4DHwith ducted air handler GMH48-**MSK4DH11 of 4 models qualify · AHRI 206724410 | 56.6(50 is the typical model of its size class)ZE-48HPBwith ducted air handler AH-48B1 of 2 models qualify · AHRI 207036646 |
| Non-ducted, up to 1.5 tons | 73.1(50 is the typical model of its size class) (higher)GXH18(5.3)FMK4DH-17 of 8 models qualify · AHRI 210276805 | 72.9(50 is the typical model of its size class)ZE-09UH24SCOwith ductless indoor unit ZE-09UH24SCI11 of 15 models qualify · AHRI 208287539 |
| Non-ducted, 2 tons | 76.1(50 is the typical model of its size class) (higher)GXH24(7.0)FMK4DH-12 of 2 models qualify · AHRI 210276806 | 64.0(50 is the typical model of its size class)ZE-24CA22SEXTwith ductless indoor unit ZE-24CA22SINT3 of 4 models qualify · AHRI 203446804 |
| Non-ducted, 2.5–3 tons | 73.7(50 is the typical model of its size class) (higher)GXH42(12.3)FMK4DH-15 of 5 models qualify · AHRI 210276804 | 64.0(50 is the typical model of its size class)ZE-36M422SCO1 of 1 models qualify · AHRI 206347270 |
| Non-ducted, 3.5–4.5 tons | No models in this size class | 41.9(50 is the typical model of its size class)ZE-42M522SCO1 of 1 models qualify · AHRI 206346135 |
All-around best
| Size and duct type | AIRTEMPAll-around score, best model | ZEPHYRAll-around score, best model |
|---|---|---|
| Ducted, up to 1.5 tons | 31.2(50 is the typical model of its size class)GXH18(5.3)FMK4DH-11 of 2 models have all five ratings · AHRI 210276818 | No models in this size class |
| Ducted, 2 tons | 60.8(50 is the typical model of its size class) (higher)GXH24-36MSK4DHwith ducted air handler GMH24-**MSK4DH12 of 3 models have all five ratings · AHRI 206724408 | 46.3(50 is the typical model of its size class)ZE-24HPBwith ducted air handler AH-24B1 of 1 models have all five ratings · AHRI 207036640 |
| Ducted, 2.5–3 tons | 53.1(50 is the typical model of its size class)GXH30(8.8)FMK4DH-13 of 6 models have all five ratings · AHRI 210276820 | 63.2(50 is the typical model of its size class) (higher)ZE-36HPBwith ducted air handler AH-36B1 of 1 models have all five ratings · AHRI 207036642 |
| Ducted, 3.5–4.5 tons | 63.3(50 is the typical model of its size class) (higher)GXH48-60MSK4DHwith ducted air handler GMH48-**MSK4DH11 of 4 models have all five ratings · AHRI 206724410 | 57.3(50 is the typical model of its size class)ZE-48HPBwith ducted air handler AH-48B2 of 2 models have all five ratings · AHRI 207036646 |
| Non-ducted, up to 1.5 tons | 58.0(50 is the typical model of its size class)GXH18(5.3)FMK4DH-18 of 8 models have all five ratings · AHRI 210276805 | 81.4(50 is the typical model of its size class) (higher)ZE-09UH24SCOwith ductless indoor unit ZE-09UH24SCI11 of 15 models have all five ratings · AHRI 208287539 |
| Non-ducted, 2 tons | 71.5(50 is the typical model of its size class) (higher)GXH24(7.0)FMK4DH-12 of 2 models have all five ratings · AHRI 210276806 | 67.5(50 is the typical model of its size class)ZE-24M322SCO3 of 4 models have all five ratings · AHRI 206346130 |
| Non-ducted, 2.5–3 tons | 70.2(50 is the typical model of its size class) (higher)GXH42(12.3)FMK4DH-15 of 5 models have all five ratings · AHRI 210276804 | 69.5(50 is the typical model of its size class)ZE-36M422SCO1 of 1 models have all five ratings · AHRI 206347270 |
| Non-ducted, 3.5–4.5 tons | No models in this size class | 44.5(50 is the typical model of its size class)ZE-42M522SCO1 of 1 models have all five ratings · AHRI 206346134 |
Standout model on each rating
Each manufacturer’s model that beats the largest share of comparable models on the rating; the higher share is in bold.
| Rating | AIRTEMP | ZEPHYR |
|---|---|---|
| COP at 5°F | beats 89% · 2.21GXH18(5.3)FMK4DH-1Non-ducted, up to 1.5 tons | beats 81% · 2.13ZE-24CA22SEXTNon-ducted, 2 tons |
| Capacity retention at 5°F | beats 85% · 89%GXH30(8.8)FMK4DH-1Ducted, 2.5–3 tons | beats 99% · 113%ZE-36M422SCONon-ducted, 2.5–3 tons |
| HSPF2 | beats 82% · 10.0GXH36(10.6)FMK4DH-1Non-ducted, 2.5–3 tons | beats 83% · 9.5ZE-36HPBDucted, 2.5–3 tons |
| SEER2 | beats 83% · 24.0GXH12(3.5)LSK4DH2Non-ducted, up to 1.5 tons | beats 89% · 25.5ZE-09UH24SCONon-ducted, up to 1.5 tons |
| EER2 | beats 84% · 12.5GXH30(8.8)FMK4DH-1Non-ducted, 2.5–3 tons | beats 89% · 14.5ZE-09UH24SCONon-ducted, up to 1.5 tons |
| Heating capacity at 5°F | beats 86% · 14,500 Btu/hGXH18(5.3)LSK4DH2Non-ducted, up to 1.5 tons | beats 92% · 18,000 Btu/hZE-18M222SCONon-ducted, up to 1.5 tons |